Use the TV as a monitor and an A/V Receiver as a switch. Plug the ATV into the A/V Receiver, and Tada! Problem solved.
All video passes through the A/V Receiver and all audio comes out through the speakers attached to the A/V Receiver.
Running Latest on:
Acer Aspire Revo 3770 (Win7 SP1 Home Prem)/46" Sharp Aquos 1080p/ Sony 7.1 STR-DG800
MacBook Pro 10.7 (Lion) Core2Duo 2.2G/4GB/17"WS/Nvidia8600M
Linux Ubuntu 11.10 (Oneiric Ocelot) P4 3.4G/2GB/22"WS Gateway/Nvidia7600GT
i7 920/6GB/23"WS LED Samsung/Win7 Pro 64/XFX Radeon 5770
Streaming (SMB) from:
unRAID NAS Server Intel i3/4GB/Intel PRO/1000 PM 11TB Disk (8TB Data/1TB Cache/2TB Parity)